Produksi Fitoaleksin pada Tusam (Pinus merkusii Jungh. et de Vriese) sebagai Respon Infeksi Fungi Mikorisa

Abstract

The experiment aimed to detect (1) mycorrhizal infection induced phytoalexins production of the root of tusam and (2) its activity in suppressing a dumping off fungi, Fusarium sp and Rhizoctonia solani. Production of phytoalexins was detected from the extracts of mycorrhizal root of old trees and 4, 6 and 8 week-old seedlings in alcohol using a UV-spectrophotometer. The antifungal activity of phytoalexins was studied by inoculating the pathogenic fungi into mycorrhizal seedlings of tusam. The results showed that the spectra of phytoalexins of extracted mycorrhizal and non-mycorrhizal roots ranged from 203.2 to 204.6 nm. Higher antifungal concentrations of antifungal compound was obtained from the root extracts of old trees and 4 week-old seedlings, indicated by the higher spectrophotometric absorbance (0.315 and 0.324 g-1 root ml-1 ethanol), compared to that extracted from non-mycorrhizal root of the same plant origin. Mycorrhizal roots significantly suppressed the development of Fusarium sp. and Rhizoctonia solani.